This genus exhibits striking sexual dimorphism in most species, with the
males smaller and darker than the females as illustrated. It was reviewed by
Holloway (1982b). The forewing venation has an areole with R2 branching off from
it subapically and R5 more or less connate or slightly stalked with R3+4. Rs and
M1 are stalked in the hindwing. The general facies, with finely striate black
irroration on the cream ground of the forewing, is distinctive.

The male abdomen contains tymbals. The genitalia are broad, the uncus
reduced, sometimes notched, and the valves are deep, with both costal and
ventral margins extended and upcurved, the latter much longer than the former.
The vinculum is broad but there is not a distinct saccus. The aedeagus is short,
apically downturned, the small vesica with a distal cluster of moderate spines.

In the female, the ductus is moderate, swollen basally but very narrow,
more distally. The ostium opens within a shield-like lamella vaginalis. The
bursa is elongate, ovate, longitudinally corrugated, with a lens-shaped
scobinate signum with a central ridge set centrally.

The type species has been reared from Quercus (Fagaceae) in India
(unpublished IIE records), and the biology of the Sundanian species is noted
below.

The relationship of the genus could be more with Arctornis and
allies than with the other major groups, though the presence of a strong cocoon
is contrary to this hypothesis. Apart from the species noted by Holloway
(1982b), Chao (1985) described two new species from Yunnan in Pida Walker
that, from their genitalia and comparison with L. epiperca Collenette (Sulawesi)
in the original description, are better placed in Locharna: L. pica Chao comb.
n. and L. flavopica Chao comb. n.. The relationship of these
species to the Chinese type species and Himalayan relatives discussed by
Holloway (1982b) needs investigation: Chao also distinguished his two species as
having yellow versus brown males. The genus does not occur east of Sulawesi.